The absolute distance scan ran at one centre on the 8 strongest of 96 sampled frames, at the run's indexing
tolerance. Three ways that found nothing, and the run then stayed at the file's value or, on an XTC, at the
100 mm placeholder:
- a sparse I-centred lattice whose file states 180 mm for a detector at ~135 mm indexed at no distance from
the background centre (7 px off) - only from the file's centre. Every centre hypothesis is now scanned;
- a 92 A cell at ~199 mm indexed on no centre 3 px off, nor at a distance half a scan step off. The scan's
frames are now indexed at tolerance 0.2 instead of 0.1; the scan only has to find the peak, and every
later step (the peaks on 32 frames, the fine step, the centre grids) counts at the run's own tolerance;
- on a run with a hit rate of a few percent the 8 strongest of 96 frames held no crystal. Where nothing
indexes at any distance at the run's tolerance, the sample is made ten times larger and the search run
again, the scan on 16 frames.
With these an LCLS XTC (no distance stated) with two crystal forms finds 198.93 mm against the 199.0 it was
given (R-free unpinned 0.236, pinned 0.238); a Rayonix CXI stating 839 mm finds 106.23 mm (0.206 vs 0.204
pinned at 105 mm); another XTC finds 193.41 against 193.43 (0.202 vs 0.200); the 180 mm file still finds
136.15 mm. Sets whose stated distance is right keep it, with unchanged results. The fallback costs ~30 s,
only where it fires.
RefineStillsGeometry also reports the slope of the indexed spots' signed excitation error against d*^2 at the
geometry it starts from: positive where the distance (and the cell) is short, negative where long. Reported
only.
The usage message and docs no longer describe --detector-distance as the joint fit's starting value (it is
held since 45abde17a), and say that an XTC with -C has its distance searched.
Co-Authored-By: Claude Opus 5.5 <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_015CeEGgpKdfkCTJb3YNMJcu
leonarski_fandClaude Opus 5.5
be45f99298
